Obesity itself is a significant public health problem and is associated with increased postmenopausal breast cancer incidence and mortality. This research proposal will assess a novel method to improve physical activity in Black women, who are generally less physically active and more overweight and obese than women of most other racial and ethnic groups. In this study we will use a novel gaming intervention strategy and assess its impact on weight and biomarkers related to obesity, insulin-related pathways and inflammation. We propose a 6 month two-arm randomized clinical intervention trial using video gaming compared to a control group. We will randomize 100 Black sedentary overweight or obese women to either the Wii Fit exercise intervention arm or the control arm. The Specific Aims of the study are: (1) to examine the feasibility and acceptability of an exergaming intervention in a community-based setting. We will assess overall accrual and adherence to the intervention regimen; (2) to explore intervention main effects of exergaming using Wii Fit on study endpoints of cardiovascular fitness and percent body fat in Black women who are sedentary and overweight or obese. To our knowledge, this is the first study investigating a video gaming intervention in adults; (3) to examine the feasibility of collecting biospecimens in a community-based setting; and (4) to explore the impact of the exergaming intervention on biomarkers.